oe chicago



. W. H. GREEN -APPARATUS AND METHOD FOR PREPARING AID rnoroanonme nosnmurxmss July 5, 1932.

Original Fiied Dec. 15, 1924 WZZZE/H Green Reissued July 5, 1932 UNITEDSTATES PATENT OFFICE WALTER E. GREEN, OF CHICAGO, ILLINOIS, ASSIGNOR,IBY ASSIGNMEN'ISfTO GENERAL ZEOLITE COMPANY, OF CHICAGO, ILLINOIS, ACORPORATION 01' ILLINOIS APPARATUS AND rm'rnon ron. rnnranme ANDPROPORTIONING nosnro xxx-rum Original No. 1,722,571, dated July 30,1929, Serial No. 765,837, filed December 15, 1924. Application forreissue filed July 29, 1831. Serial No. 553,868.

This invention relates to porportionate feed apparatus for combiningdifierent materials in predetermined proportions and in which the rateof supply of one of the 5 materials is regulated or controlled inaccordance with the rate of supply ofthe other, so that the combining ofthe materials may be carried on continuously and in constant proportionirrespective of variations in the rate of supply of the controlmaterial. in the feeding of reagents to water, incident to treatment forremoval of hardening or scale forming ingredients. It has to do,however, with more than the mere proportioning of the materials, as itinvolves also the preparation of the treating or dosing mixture, withthe purpose of controlling or regulating the rate at which it isprepared, in accordance with the rate of supply of the water to betreated.

The rate at which water is suppliedfor commercial use, such as for steammaking, laundering or the like,is subject to variation in the demand orrequirements and in the supply pressure. Proper and uniform treatment ofthe water requires uniformity in the proportioning of the treatingmaterial to the raw water. Of course, a large supply of treatingmaterial maybe made up ahead of time to be. drawn upon in accordancewith the momentary -demand over a period of time. That procedure,

the prepared 'materials and a fore-hand knowledge of the approximaterequirements.

It is an object of the present invention to obtain the desired result inproportionate combining of materials more directly, by controllingautomatically the preparation of the treating mixture directly from theraw commercial materials- The material most It finds a particularapplication.

tion of these from the end product.

however, requires a large storage space for.

method of procedure which is continuous,

sufliciently rapid to meet the requirements of the water supplied fortreatment and susceptible of automatic control in accordance with therate at which the wateris supplied.

Inasmuch as unslaked lime in its crude commercial form customarilycontains more or less refuse matter in the form of gravel, sand andunreduced limestone, it isimportant that provision be made for thesepara- Consequently one of the objects of the invention is an apparatusin which that result may be attained in such fashion as to permitcontinuous operation of the apparatus through extended periods of time.

Other and further objects of the invention will be pointed outhereinafter, indicated in the appended claims or obvious to one skilledin the art upon an understanding of the present disclosure. For thepurpose of this application I have elected to explain the invention byreference to an illustrative structure. It is to be understood, however,that the representation of means is merely diagrammatic or schematic, asthe results may be attained in substantially the same fashion-byvarious. organizations of divers mechanical elements and devices nowknown in the art.

In the drawing forming a part of this specification:

Fig. 1 is a diagrammatic illustration representative of a. longitudinalsectional elevation of apparatus illustrating the practice of theinvention.

Fig. 2 is an elevation detail of speed con trol mechanism.

The nature of the invention probably will best be understood byreference to the illustrative means. Referring, to the drawing, let itbe understood that the numeral 10 designates a tank of horizontalelongated proportion and of semi-cylindrical sectional form. Referencecharacter ll designates a ment of a discharge element 12" A device ofthis general type is known in the art, but' it is here presented simplyas illustrative of any suitable form of controlled feed supply,mechanism. Reference numeral 14 designates a water supply apparatus,the same being represented in the formof a tank in which a constantlevel of 'water is main: tained through operation of the: floatcontrolled valve 15 of a supply line 16. This water supply deviceincludes a variable discharge element 17, represented as a swingingoutlet pipe, the inlet end of which is provided with an inlet orificeand may be raised and lowered in the water in tank 14 so as to vary thehead on the orifice and thereby vary the rate of discharge therethrough.Water discharged through pipe 17 is delivered to pipe 18 and dividedbetween pipes 19 and 20 1n accordance with the setting of a regulatingvalve 21. Pipe 18 has an air vent 18 to allow for air compensation inipes 17 and 18. 'Pipe 19 leads to the supp y end ofthe tank 10, so thatthe water delivered thereby will be brought into contact with theunslaked lime supplied by the device 12. The

setting of the regulating, valve 21 is-such as to apportion to the pipe19 an amount of water adequate to hydrate the lime at the rate at whichit issupplied by the supply mechanism 12, and to form a plastic mixturewith it, but without materially reducing the heat generated 'by thereaction of the water and the lime. Of course this amount of water isvery much less than that necessary to form the desired treatingmaterial, but

' the purpose of so limiting it is to permit the slakmg process toproceed at the most expeditious rate. The water and the lime areagitated and mixed together by stirring members 22 which are actuated bythe shaft 24. These stirring members are formed so as to induce agradual progressive feed of material away from the supply end of thetank and toward a partition 25. The length of the tanks is such thatwhen the mixture artition 25 it is in a uniform plastic condition andthe lime is hydrated. The shaft actuates the revolving dippers 26 whichdip the mixture out of the slaking compartment 10 and discharge it overthe partition 25 into the mixing compartment 10". The discharge capacityof the dippers 26 is adequate to handle the maximum supply capacity ofthe mechanism 12 and pipe 19 during a given period of time at a correl-5 ative speed. The capacity of the dippers to discharge material fromcompartment 1Q must be greater than the'rate of supply of materials intothe compartment. This is so that there will be no tendency for materialto collect in quantities in chamber 10'. The

material should be discharged into 10 as soon as the slaking operationhas been completed. The actual discharge capacity of the dippers 26depends upon the rate of revolution in the shaft 24 and size of thedippers. The rate of revolution in this shaft i's'proportionate to therate at which I the materials are supplied to slaking chamber 10. Thereis no limit to the size or holding capacity of the dippers 26, except arestriction due to the size of the apparatus, for they cannot feedmaterial out of chamber 10 any faster than it comes to them. Inpreferred construction they should come up about half or two thirdsfull. It is important that-they should iiever come up completely filled,incapable of elevating and transferring more material since if this wasthe case there would be inevitably a building up of materials in thechamber 10. Here it I is mixed with a much larger proportion of water,supplied through the pipe 20, and-- stirred up by the action of theheaters 27 to form a homogeneous liquid, or milk of lime, which it isnow qualified to do'readily by virtue of-the hydrated condition of thelime. This milk of lime seeks its level in'the mixing compartment 10",the baflle 28 being interposed in the compartment to prevent the passageof the incoming water directly to the discharge end of the compartment.Any refuse, such as gravel or sand, which is fed in with the unslakedlime, is fed along with the materials incident to the slaking operationin compartment 10, and is discharged therewith into compartment 10". Inthe latter compartment it sinks to the bottom of 'Tank 10 is providedwith a discharge over a long horizontal edge 32 across the width of thetank, whichpermits passage of the treating mixture from the compartment10 to the feed pipe 34, whence it is conducted to the water to betreated. Obviously the rate of discharge over the edge 32,willdependupon the rate at which materials are supplied into compartment10". This is determined by the rate of supply from the'feeding means 12and tank 14. of the slaked lime to compartment 10 is dependent on thespeed of the shaft 24, and the setting of the element 12, while the rateof water feed is depen ton the elevation l The rate of feed compartment10", may be effected automati of pipe 17. Consequently, in order toaccommodate the Varying requirements for treating liquid, there must bevariations in the rate at whichthe unslaked lime and the water aresupplied to the mixing compartments. The latter is taken, care of bythe. adjustment of the orifice 17" at the end of pipe 17. The amount ofliquid flowing into pipe 17 through the orifice 17 will be controlled bythe elevation of the orifice in the tank 14. The elevation willdetermine the head of liquid upon the orifice 17 a at the end of pipe17. There is provided 'a free discharge of water into the air at theoutlet side of the orifice- (that is on the inside of the pipe) and thiswill continue so long as the pipe 17 and the other pipes farther on aresufliciently large so that the liquid flowing through the orifice iscarried away without filling them. Since a restriction may be introducedfarther along the pipe by the valve 21 the vent l8 'isprovided attachedto top of pipe 18 and extending above the liquid level in 14. This willadmit air into pipe 18. As long as the valve 21 is open sufliciently topermit the liquid to discharge through it faster than it enters theorifice 17, the variation in water supply will be controlledsatisfactorily. The variations in the rate of supply of unslaked lime'are'taken care of by variations in the speed of the supply mechanismThe latter is made tovary with the speed of the shaft 24, which speedalso determines the rate at which the materials are fed longitudinallyin the slaking compartment 10" and delivered to compartment 10 In orderthat these variations, which have the final objective of varying therate of discharge of the treating mixture from mixing cally and inaccordance with the variations in the rate of raw water supply,,regulating mechanism is provided which is responsive to the rate ofwater supply. This is illustrated by the float 50 which rises and fallswith variations in the water supply, and which is connected by suitabletransmission means 36 with the discharge pipe 17 and with speed controlmechanism which regulates the speed of the shaft 21. The speed controlmechanism is represented in Fig. 2 by ratchet wheel 38 connected withshaft 24, an actuating wheel 39 which is constantly driven from asuitable source of power to oscillate a dog' 40 to rotate the ratchet.wheel. and throw-off element 451, the position of which is variable toregulate the effective throw of the dog through movement of a sectorplate 35 by the transmission means 36. The weight of the swinging leadpipe 17 and the weight of the float 50 are-adjusted so that the float,buoyed by the body of liquid in the container 11, will just aboutbalance the swinging pipe submerged apparent.

in the body of liquid in the container 14.-

The amount of friction encountered by the transmission means 36 inpassin over the pulleys and the sector plate 35 Wlll prevent anymovement thereof without a change in the level of the liquid in the tank11 and a resultant change in the position of the float 50. Thetransmission means 36, which consists of a wire or cord is maintained insuch frictional relationship with the sector 35 that a movement of thetransmission means 36 will result in a corresponding movement of thesector 35. Since the sector 35 is rigidly attached to the throw-01felement 41, the throw-off element will be correspondingly shifted inposition with every movement of the transmission means 36. The positionof the throw-off element 41 will determine the amount of movement of'theratchet wheel 38. The movement of the ratchet wheel 38 results from themovement of the dog 40 to the left while in operating engagement withthe teeth on theperiphery of the ratchet wheel 38. The movement of thedog is constant but the portion of the movement in which it is inoperating engagement with the ratchet wheel 38 may be varied by changingthe position of the element 41. If the throw-off element 41 were movedfarther to the left than as shown in Figure 2, the portion of the throwof the dog 40 in which it was in engagement with the ratchet wheel 38would be decreased. It is possible to .move the element 41 far enough tothe left so that the dog 40 will be kept out of engagement with theratchet wheel 38 during actuating contact therewith fora greater arc. Itis apparent that if the element 41 is moved far enough to the right, itwould be possible for the dog 40 to be in actuating relation with theratchet wheel 38 during its entire leftward movement.

The operation of the speed regulating devices shown upon Figures 1 and 2is readily The liquid in the. container 11 represents the raw water. Theraw water flows toward the left and milk of lime is added to it at apoint below .the pipe 34. The mixture finally flows over a weir or someother retarding means 11a atthe left end of the container 11. The levelof liquid in the container or conduit 11 will correspond to the rate offlow therein and will bear some fixed relationship thereto.

It is obvious thatwith an increased rate of flow it is desirable to addmore milk of lime to the water while with a decreased rate of flow itwill be desirable to add less milk of lime to the water. This isaccomiso plished in the followin manner: If there is an increased rateof ow, the level in the container or conduit 11 will be higher, raisingthe float 50.v Whereupon the transmisv longer portion of its throw. Thiswill cause a faster movement of shaft 24 and an increase in the rate offeed of lime to the chamber 10. The lowering of the orifice 17 will alsoincrease the head of liquid thereupon, which in turn will increase theamount of Water flowing down through lines 18, 19 and 20. Asa result,more lime will be slaked in chamber 10, more slaked lime will beconverted into milk of lime in chamber 10, and more milk of lime willflow over the orifice 32 into the conduit 34 and finally into the rawwater passing through the conduit 11.

If the raw water passing through the conduit or container 11 decreases,the level of liquid will decrease and the float will be lowered.Whereupon the transmission means 36 will elevate the swinging pipe 17and will move the throw-01f element 41 to the left. The elevation of theinlet orifice in the swinging pipe 17 will decrease the head thereuponand result in a decreased flow of slaking and diluting water throughlines 19 and 20 respectively. The movement of the throw-off element 41to the left will decrease the arc in which the dog 14 is in actuatingengagement with the ratchet wheel 38 and this will decrease the speed ofthe shaft 24., With the decrease in the speed of the shaft;;24, lessunslaked lime will be fed into the sl aking chamber 10, less slaked limewill be fed into the diluting chamber or milk 'of lime chamber 10 bymeans of the cups 26, and less milk of lime will flow over thehorizontal orifice 32 to be intermixed with the water flowing throughthe conduit 11. When the flow of liquid through the conduit 11 hasceased, the float 50 will ride in such a lowered position that thetransmis sion means 36 will lift the orifice 17 out of the body ofliquid in the basin 14 and will also move the throw-off element 41 asufficient distance to the left to prevent the dog 40 from coming intoactuatingengagement with the ratchet wheel at any portion of its throw.As a result, no water will flow through lines 18,19 or 20, no unslakedlime will be fed into the slaking'chamber 10 and no slaked lime will befed into the diluting chamber 10". The power shaft on which the powerwheel 39 is positioned is separately controlled and may also be stoppedby means not shown.

As long as the dog 40 is out of actuating movement of the shaft 24 willtake place since the pedals are immersed in'thick heavy lime in'cha-mberl0. Thewresistance of the semi-solid in chamber 10 and the liquid inchamber 10 will be sufiicient to stop rotation immediately upon releaseofthe pawl or dog 40. I

It will be noted that not only the supply of raw materials isautomatically regulated and controlled in accordance with the variationsand supply of raw water, butalso the rate at which the n aterials aretransmitted through the apparatus and the refuse removed is controlledthereby. The final result. is the automatic control of the feed of thedosing mixture to the raw water in accordance with the rate at which thelatter 1S supplied. 7

Of course, it is not essential-that the regulation of the lime and Waterfeed be controlled automatically. By a fixed setting of means 36 or ofthe element 41 and pipe 17 so as to eliminate the control by float 50,the

feed of material may be held constant, with the result that thedischarge from compartment 10 will be held constant. In sucharrangement, it will be observed, the feed of the treating material iscontrolled by the rate of feed of the unslaked lime and water to theapparatus.

I claim:

'1. A method of preparing and proportioning a dosing mixture, comprisingfeeding unslaked lime and Water together in predetermined proportion ata rate controlled by the raw water supply, stirring the water and limeengagement with the ratchet wheel 38 no i to induce hydration of thelatter, feeding the a slaked lime and more water at a rate correspondingto that of the original lime and water supply, agitating the slaked limeand water to form milk of lime and' delivering the latter to the rawwater at a rate corresponding to its rate of preparation.

2. A method of preparing and proportioning a dosing mixture whichcomprises slaking lime, adding water thereto and agitating to form milkof lime, feeding the latter to the raw water in accordance with'the rateat which. it is prepared,.,and controlling said feeding by the rate offlow of the water to be'dosed.

3. A method of preparing and proportioning a dosing mixture, comprisingslaking lime with water, mixing the slaked lime with more water to makemilk of lime, feeding the mixture to the raw water, controlling the,rate of such feeding by the rate of lime and water supply, andproportioning the rate of lime and water supply to the .rate of rawwater feed.

4. A method of preparing and proportioning a dosing mixture, comprisingfeeding lime and water together to hydrate the lime, feeding thehydrated lime and water lime, removing refuse from the mixture incidentto its preparation, and delivering the together to form milk of lime,-delivering the latter at its, rate of preparation, and

mixture to the raw water in conformity with its rate of preparation.

{3. A water softenin process which comprises providing supp ies of rawwater to be treated, unslaked lime to be prepared for admixture withsuch raw water, and Water to be admixed with the lime during suchpreparation, admixing the unslaked lime and the last mentioned Water ata rate proportionate to the rate of supply of the raw water, addingfurther qauntities of the same water to the resultant mixture and thenadding the final mixture to the raw water supply.

7. A water softening process which comprises providing supplies of rawwater to be treated unslaked lime to be prepared for. admixture withsuch raw water, and water to be admixed with the lime during suchpreparation, admixing the unslaked lime and the last mentioned water inquantities insuflicient to decrease materially the heat of the resultingreaction at a rate proportionate to the rate of supply of the raw water,adding further quantities of the same water to. dilute the resultantmixture and then adding the final mixture to the raw water supply.

A water softening process which comprises providing supplies ofraw waterto 0 treated, unslaked lime to'be prepared for admixture with such rawwater, and water to be admixed with thelime during such preparation,admixing the unslaked lime and the last mentioned water in quantitiessufficient to slake the lime without excessively diluting the resultantslaked lime at a rate proportionate to the rate of supply of the rawwater, adding further quantities of the same water to dilute theresultant mixture and then adding the final mixture to the raw watersupply.

S). A water softening process which comprises providing supplies of rawwater to be treated, unslaked lime to be prepared for ad- 0 mixture withsuch raw water, and suppliesof water to be admixed with the lime duringthe different stages of such preparation,

adding together the unslaked lime with suftheaddition of water to theunslaked lime to form slaked lime, the addition of water to the slakedlime to form milk of. lime, the addition of unslaked lime to form slakedlime, the addition of slaked lime to form milk of lime and theaddition'of milk of lime to the raw water to be treated by the rate offlow of the raw water.

10. A water softening process which'comprises providing supplies of rawwater to be treated, unslaked lime to be prepared for admixture withsuch raw water, and sup-' plies of water to be admixed with the limeduring the different stages of such preparation, adding together theunslaked lime with suflicient water to slake the same, adding togethersufficient water and the slaked lime to form milk of lime, adding thefinal mixture to the raw water supply and regulating the addition ofwater -to the unslaked lime to form slaked lime, the addition of waterto the slaked lime to form milk of lime, the addition of unslaked limeto form slaked lime, and the addition of slaked lime to form milk oflime by the raw water supply and converting the slaked lime into of limeand adding the milk of lime to the raw Water supply substantially assoon or shortly after they are formed without storof the tank, means fordiluting the milk of lime mixture discharge from said last-namedmeans'with a further quantity of water, a

raw water supply,-and means for adding said diluted mixture to the rawwater supply.

12. A method of treating water, which comprises continously feedingunslaked lime and water together at set rates to slake the lime and formtherefrom a fluid slaked lime- 'water mixture, agitating the materialswhile undergoing the slaking reaction, continuously removing the fluidslaked lime-water mixture from the slaking zone at the rate it is beingslaked whilecontinuously separating refuse from the-fluid slakedlime-water mixture, continuously mixing additional water with theremoved mixture to produce therefrom a diluted lime suspension, andcontinuously delivering the diluted lime suspension at the rate 'of itsproduction to the water to be treated 13. A water treating process,which comprises slaking lime with water, mixing the slaked lime withmore water to form milk of lime, feeding-the milk of lime to the rawwater, controllingthe rate of such feeding by the rate of lime supplyand water, and

proportioning the rate of lime supply to the water feed.

15. A method of treating water, which comprises continuously feedingunslaked lime and a relatively small amount of water together at setratesto hydrate the unslaked lime and to form therewith milk of lime,the proportions of unslaked lime and water being such as to maintain inthe slaking zone asubstantially increased temperature from the reactionof the materials, agitating the materials while undergoing the slakingreaction, continuously removing the milk of lime from the slaking zoneat the rate of its formation, and continuously supplying the milk oflime to the water that is to be treated at the rate that the milk oflime is removed from. the slaking zone.

16. A method of treating water, which comprises maintaining a body ofmilk of lime at an elevated temperature, continuously feeding unslakedlime and water together and into said body of milk of lime to ydrate theunslaked lime and to form therewith additional milk of lime, agitatingthe materials while undergoing the slaking reaction, continuouslyremoving milk of lime from said bodyrat the rate of its formation, andcontinuously supplying the removed milk of lime directly to the water tobe treated at the rate of its removal.

17. A method of treating water, which comprises maintaining a body ofmilk of lime, continuously feeding water and untreated.

slaked lime containing insoluble refuse toydrate the unslaked lime andto form additional 'milk of lime, agitatin the materials undergoingthe-slaking reaction, separating the refuse from the milk of lime,continuously removing milk of lime from said body, and continuouslysupplyin the removed milk of lime directly to t e water to be 7 18. Amethod of treating water, which comprises maintaining a body of milk oflime, continuously feeding unslaked lime and-a relatively small amountof water into said body of milk-of lime to hydrate the unslaked lime andto form additional milk of 65 lime, the proportions of unslaked lime andwater being such as to maintain the slaking zone of said body of milk oflime at a substantially increased temperature from the reaction of thematerials, agitating the materials during the slaking reaction,continutreated.

ther and into said body of milk of lime to ously removing milk of limefrom said body, and continuously supplying the removed milkof limedirectly to the water to be 19. A method ,of treating water, which"comprises continuously feeding unslaked lime and a relatively smallamount of wa ter together at set rates to hydrate theunslaked lime andto formtherewith milk of lime, the proportions of unslaked lime andwater being such as to maintain in the slaking zone a substantiallyincreased temperature, agitating the materials whileundergos ing theslaking reaction, continuously removing the milk of lime from theslaking zone, adding more water to said removed milk of lime, andcontinuously adding the milk of lime directly to the water to betreated. a v

20. A Water treating apparatus, comprising a tank for holdin asubstantial quantity of liquid, means or continuously supplying unslakedlime to said tank, means for continuously supplying water to said tank,means in said tank for agitating said unslaked lime and'water to hydratesaid unslaked lime and to form therewith milk of lime, a raw watersupply system, means for continuously adding said milk of lime directlyto water in sald raw water supply system at the rate of formation ofsaid milk of lime, and means responsive to changes in the rate of flowof raw water through said system for controlling said unslaked limesupply means. F

21. Apparatus for treating water, comprising a slaking tank for holdinga substantial quantity of liquid, means for adding a continuous supplyof unslaked lime in lump form and containing appreciable quantities ofinsoluble refuse to said slaking tank, means for adding a continuoussupply of water to-said slaking tank to hydrate said lime and to formtherewith milk of lime, a rotatable shaft mounted in said tank, spacedradial arms mounted on said shaft to provide agitating V means in saidtank, a raw water supply sys-' tem, and means for continuously addingthe milk of lime from the slaking tank directly to the raw water supplysystem and at a rate substantially equal to the rateof formation of milkof lime.

- spaced radial arms mounted on said shaft to provide agitating means insaid tank, means forremovmgtherefuse from the slaln'ng tank andifrom themilklof lime, .a raw water sup ply system and means forlcontinuouslyadding said milk of lime directly tothe raw water supply system at arate substantially equal to the rate of formation of milk of lime.

23 Apparatus for treating water, comprising a tank for holding asubstantial quantity of liquid, means for continuously adding a supplyof unslaked lime to said tank, means for adding a continuous supply ofwater to said tank to hydrate said lime and form therewith milk of lime,a rotatable shaft in said tank, spaced radial arms mounted on said shaftto provide agitating means in said tank, means for diluting said milk oflime,

a raw water supply system, and means for continuously adding the dilutedmilk of lime directly to said raw water supply at a rate substantiallyequal to the rate of formation of milkof lime.

24:. A water treating apparatus, comprising-an unslaked lime treatingtank having an overflow outlet in the upper portionthereof, means forcontinuously adding a supply of unslaked lime to said tank, means forcon- 25 tinuously supplying water to said tank to hydrate said lime andto form therewith milk of lime, a rotatable shaft in said tank, spacedagitators extending from said shaft, and a raw water supply systemcommunicating with the overflow of said tank, said raw water supplsystem receiving milk of lime displace from said tank.

25. A water'treating apparatus, comprising a tank for holding a body ofliquid, means for continuously adding a supply of unslaked lime to saidtank, means for adding a continuous supply of water to said tank tohydrate said lime and to form therewith milk of lime,

agitating means for said tank, means for removing milk of lime from saidtank at the rate of formation of the ,milk of lime, means for dilutingsaid milk of lime, a raw water supply system, and means for continuouslyadding the diluted milk of lime directly to said raw water supplysystem.

In testimony whereof, I have hereunto subscribed my name. WALTER H.GREEN.

